-LRB- CNN -RRB- -- A U.S. destroyer is shadowing a ship off the coast of Somalia after it was taken over by 50 pirates , authorities said .

The M/V Iceberg was identified last week after the USS McFaul conducted a 36-hour surveillance mission , the multi-national Combined Maritime Forces said in a statement . The USS McFaul began shadowing the Panamanian-flagged vessel May 19 before the M/V Iceberg reversed course and began heading toward the Somali coast .

`` We can not be sure what the pirates ' plan was if they had not been interrupted , '' said Rear Adm. Beom Rim Lee , commander of the Combined Maritime Forces task force .

`` The vessel may have been on its way to either assist other pirates in distress , or look for another merchant vessel to attack , '' he said .

The M/V Iceberg was last been seen off the coast of the Somali town of Garacaad , a known pirate haven , but its exact location was unknown until USS McFaul positively identified it . `` Further investigation showed the name of the ship had been crudely painted over '' in an effort to disguise it , which caused confusion in identifying it , the Combined Maritime Forces statement said .

The USS McFaul had initially requested to board the ship to check on the crew . The M/V Iceberg denied it had been taken over , saying it was having mechanical difficulties . Eventually , crew members radioed back saying they had been taken hostage by heavily armed pirates , officials said .

The M/V Iceberg has a crew of 24 from Yemen , India , Ghana , Sudan , Pakistan and the Philippines , officials said .

Cmdr. Ronald W. Toland , Jr. , commanding officer of USS McFaul , said he tried to ensure the safety of the crew first .

`` Given the report of heavily armed pirates on board , it was more prudent to monitor the ship 's movement , rather than attempt a rescue , '' he said .

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Destroyer USS McFaul followed Panamanian vessel as it headed toward Somalia

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M/V Iceberg and crew of 24 are held by 50 pirates

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U.S. ship commander putting off rescue attempt out of concern for captives ' safety